Process of forming agglomerated carbon black



March 12,- 1940.

H. W. GROTE PROCESS OF FORMING AGGLOMERATED CARBON BLACK Original Filed Aug. 22, 1933 INVENTOR. Gr l? A ITORNEYS.

Reiaued Mar. 12, 1940 I I f R 21,390

UNITED STATES PATENT OFFICE PROCESS OF FORMING AGGLOMERATED CARBON BLACK ,l-lans Walter Grote, New York, N. Y., assignor to United Carbon Company, Inc., Baltimore, Md., .acorporation oi Maryland Original No. 2,040,710, dated May 12, 1936, Serial No. 686,311, August 22, 1933. Application for reissue September 27, 1937, Serial No. 165,943

7 10 Claims. (Cl. 13460) The present invention relates to the produ cshaped device, having agitators also acting as tion of agglomerates or shaped masses of carbon propellers C. Jets of a suitable vapor or liquid black, for the purpose of overcoming some of the or mist are directed up n the material from the objectionable properties of raw carbon black, such spayers or perforated pipes D, and the proportion as the formation of dust, during the handling of of the liquid used should be such as to give a very 6 the same, during the mixing of the same: with friable relatively dry pasty mass, in the mixer B.

' rubber or other materials, and for producing a From the bottom of the .mixer B, the pasty product which is easier to handle. As is well mass is discharged through the chute illustrated,

known, carbon black in its original form is a or in any other manner, into the space between l0 powdery or more or less lumpy material conthe rolls of aroller mill, shown atE and F. These 10 stituted oi extremelysmail particles, so thatdurrolls rotate, in the directionof the arrows shown, ing the handling of the same, air currents may the peripheraMpeed of .one roller may be slightly blow the same about to some extent, and the greater than that of the other so that the moisobject of the present invention is to produce agtened carbon forms in a layer G, upon the roller it glomerates which will be i'reefrom the said ob- F. The thickness of this layer will be regulated ll jection. g by the space between the two rollers, this being In accordance with the present invention, .the adjustable by means of a screw shown convencarbon black is moistened with a volatile liquid, tionally at H. Y Y e. g., alcohol, benzoi, gasoline, methanol and ace- At I is shown a rapidly rotating roller, which tone, but for which purpose water is entirely suitcan rotate for example in the direction shown m able, the mass is stirred and kneaded, to form by the arrow K, the surface of the roller carrya rather stiil' paste, which is friable in character. ing a great number of small needle-shaped spikes The said paste is then worked upon an ordinary J. These needles, which are distributed over the roller mill, for example a mill consisting of two entire face of the roller 1, scratch oi! the layer u horizontal rollers rotating in a vertical plane, the or cake of compressed moistened carbon from rollers may be operated at slightly different sur the surface of the roller F, this then flowing down face'speedain order to cause the roll-milled mathrough the chute L, into the upper end of a mterial to adhere to one of the rollers, as a comtary drier M, in which the material is dried by pacted layer. when this has been accomplished, being subjected to gases at a high temperature,

another roller carrying needles or other pointsof say 400 to 500 F. in order to rapidly dry the same, similar character is rotated in such a position and leave the desirable porous friable structure of that the needles will scratch of! the material on the finished-material. the roller, thereby producing shaped masses of The roller Ishould be situated near enough to the carbon-black; which are then subjected to a the roller F so that the needles will scrape oil high temperature drying operatiompreferably at substantially the whole of the layer of carbon a p rature very m o e t boiling point therefrom, the position of said roller being adof the wetting agent employed. justed by means of a screw shown at N, or other- The dried material so produced can then be wise. The closeness together of the needles J will passed over a series of sieves in-order to separate regulate the size of the particles torn oil! in this 40 the same into different sizes, as required for difmanner, which particles will of course be of more ferent particular purposes for which the carbon or less irregular shape. black is to be employed. After the dryins p rat n th s a f'ma- For carrying out the process of the present apterial can be passed over a series of sieves, to

, plicaticn, an apparatus can be employed such .as separate the same into different particle sizes, and i is shown diagrammatically in the annexed drawany particles which are too small for use, as well 4 ing, the figure representing a sectional elevation as any particles which are too large for use, can

of suitable apparatus It is to be understood how-- be reintroduced through the conveyer A into the ever that this apparatus is shown merely for the mixer W of illustration, and not as limiting the T Dari-101G size will be in P511; mated y scope of the invention thereto. a l the thickness of the layer G on the roller F, and o In carrying out the process of the present infor ordinary purposes I find-that this layer can vention, thecarbon black maybefed through a be from a sixteenth of an inch'in thickness to conveyor A, which may be water-jacketed if dea quarter qfan inch, but -I do not restrict myself sired for cooling purposes, the carbon black fallto these limits. If any of the moistened carbon ,'ingintothemixe|-Bwhi4:l\ maybeatroughlsleftontherollerlh'aiterpassingtherollei-L this does no particular harm and will bond with I a subsequently applied layer of the paste, to be scratched off during a subsequent rotation 01' the roller.

The proportion .of water or other liquid introduced into the carbon black in the mixer B is subject to variation, and for ordinary purposes I find that about of moisture is very satisfactory. This figure however is given merely by way of illustrationwithout restricting the invention thereto.

I claim:

1. The process of converting finely divided and dusty carbon black into aproduct which is substantially dustless, comprising moistening carbon black with a volatile liquid, forming a thin sheet of the moistened carbon black, subdividing said sheet into small irregularly shaped masses of carbon black agglomerates and drying the said masses, whereby a granular product is formed which is substantially dustless.

2. The process of converting finely divided and dusty carbon black into a product which is substantially dustless,, comprising moistening the carbon black with water to form a stifi, pasty mass, forming a compressed sheet of the mostened carbon black, subdividing said sheet into small irregularly shaped masses of carbon black agglomerates and drying the said masses, whereby a granular product is formed which is substantially dustless. 7

3. The process of converting finely divided and dusty carbon black into a product which is substantially dustless, comprising moistening carbon black with water, the amount of water being about 40% of the moistened mass, forming a compressed thin sheet of the moistened carbon black, subdividing said sheet into small irregularly shaped masses of carbon black agglomerates and drying the said masses, whereby a granular product is formed which is substantially dustless.

4. The process of converting finely divided and dusty carbon black into a product which is substantially dustless, comprising moistening carbon black with a volatile liquid, forming a thin sheet of the moistened carbon black, subdividing said sheet into small irregularly shaped masses of carbon black agglomerates, and subjecting the said masses to temperatures within the range of approximately 400 to 500 F. while agitating the masses by a rotary tumbling motion to thereby dry the masses as shaped porous, friable granules of substantially dustless carbon black.

5. The process of converting finely divided and dusty carbon black into a product which is substantialy dustless, comprising moistening the carbon black with water to form a stifl, pasty mass,

forming a compressed sheet of the moistened carbon black, subdividing said sheet into small irregularly shaped masses of carbon black agglomcrates, and subjecting the said masses to temperatures within the range of approximately 400 to 500 F. while agitating the masses by a rotary tumbling motion to thereby dry the masses as shapedporous, friable granules of substantially dustless carbon black.

6. The process of converting finely divided and dusty carbon black into a product which is substantially dustless, comprising moistening carbon black with a volatile non-solvent wetting agent and working the mass to form'a friable relatively dry paste, subjecting the wetted mass to roll millatures within the range of approximately 400 to 500 F., whereby substantially dry, porous, friable granules of a substantially dustless product are formed.

7. The process of converting finely divided and dusty carbon black into a product which is substantially dustless, comprising moistening the carbon black with water and working the mass to form a stiff paste, subjecting said paste to rolling pressures by a pressure-exerting roller member to compress the mass and form a sheet-like compacted layer therefrom, breaking said compacted sheet-like layer into small shaped masses of wetted carbon black agglomerates, and thereafter drying the said small shaped masses of wetted carbon black at temperatures within the range of approximately 400 to 500 F. while agitating the masses by a rotary tumbling motion,

whereby a substantially dry, porous, friable granular product is formed which is substantially dustless. 1

8. The process of converting finely divided and dusty carbon black into a product which is substantially dustless, comprising moistening carbon black with approximately 40% by weight of water and working the mass, subjecting the moistened carbon black to rolling pressures by a pressureform a sheet-like compacted layer therefrom,

breaking said compacted sheet-like layer into 1 of occluded gases, which includes the steps of L mixing carbon black and a non-solvent liquid wetting agent to form a pasty mass, forming the pasty mass into a compressed sheet-like layer by subjecting it to rolling pressures by a pressureexerting roller member, subdividing said layer to form small aggregates thereof, and thereafter drying the said aggregates at temperatures within the range of approximately 400 to 500 F. while subjecting the aggregates to a rotary tumbling motion, whereby a substantially dry, porous, friable granular product is formed which is substantially dustless; I

10. The method of making minute aggregates of dustless carbon black, which includes the steps of mixing dry carbon black and a liquid wetting agent to form a pasty mass, rolling the mass with a pressure-exerting roller member to form a sheet-like layer therefrom, subdividing said layer to form small aggregates of the carbon black and liquid, and thereafter drying said aggregates by removing the liquid wetting agent at temperatures within the range of approximately 400 to 500 F. while subjecting the aggregates to a rotary tumbling motion, whereby substantially dry, po-

rous; friable granular dustless particles of carbon exerting roller member to compress the mass and 

